Implantable prosthesis having acellular tissue attachments

ABSTRACT

Improved prostheses comprising a tissue expander and a graft material are disclosed herein. Also disclosed are methods of making prostheses and methods of treatment using the prostheses.

Disclosed herein are implantable prostheses, such as breast implants andtissue expanders, for use in various surgical procedures.

Implantable prostheses, such as breast implants and tissue expanders,are used in a wide range of surgical procedures. For example, theprostheses can be used for breast augmentation, reconstruction, and/orrevision. But, even though the implants and tissue expanders used inthese surgical procedures are biocompatible and non-reactive,post-surgical complications can still result from their use, such ascapsular contracture, scar formation, implant displacement, rippling,and palpability of implants. Research has focused on surgical techniquesand modified implant characteristics, which may result in reducedincidence of complications. One approach that surgeons use to improveoutcomes, reduce the risk of complications, and/or provide improvedrevisions is to use graft materials, such as acellular dermal tissuematrices like ALLODERM® or STRATTICE™ (LIFECELL CORPORATION, Branchburg,N.J.), along with the tissue expanders or breast implants.

The current standard of care during surgical breast procedures involvesseparately attaching a graft material to a patient and then placing aprosthesis in the patient. In one procedure the surgeon first attachesthe graft material to the infra mammary fold (IMF) and the pectoralismajor muscle in order to create a submuscular pocket or flap. Next, thesurgeon places the breast implant or tissue expander inside the pocket.The process of attaching the graft material to the native tissue canrequire a substantial amount of time and involve the use of sutures orother devices to anchor the graft material to the native tissue. Thecurrent process can also lead to inconsistent results, as inexperiencedsurgeons may not use graft materials of optimal shape, or mayincorrectly position the implant or tissue expander relative to thegraft material.

Accordingly, there is a need for improved prostheses comprising tissueexpanders, methods of making these prostheses, and methods of treatmentusing such prostheses.

In various embodiments, an implantable prosthesis is disclosed herein,comprising a tissue expander and one or more samples of graft material,wherein the tissue expander is attached to the one or more samples ofgraft material in a manner that allows the tissue expander and the oneor more samples of graft material to be implanted in a patient as aunitary prosthesis, and wherein the implant or tissue expander isattached to the one or more samples of graft material in a manner thatwill allow the tissue expander and the graft material to be easilyseparated naturally or through surgical intervention after a period oftime following implantation. In some embodiments, the prosthesiscomprises molded grooves, slots, channels or other shallow cavity spacesthat secure the graft material to the tissue expander. In certainembodiments, the prosthesis comprises a biocompatible flap or pocket onthe surface of the tissue expander that secures the graft material tothe tissue expander.

In some embodiments, the prosthesis comprises one or more fixation tackscomprising one or more thin strands of biocompatible material and one ormore barbs that secure the graft material to the tissue expander. Insome embodiments, the prosthesis comprises one or more zip ties thatsecure the graft material to the tissue expander. In some embodiments,the one or more samples of graft material comprise one or more holes,slits, or apertures through which the one or more fixation tacks or zipties are passed to secure the graft material to the tissue expander.

In certain embodiments, the prosthesis comprises a belt that secures thegraft material to the tissue expander. In some embodiments, the beltcomprises slots, and the graft material is shaped to provide tabs orother shapes that will fit within the slots on the belt, therebysecuring the graft material to the belt.

In some embodiments, the prosthesis comprises attachment points, whereinthe attachment points comprise a dissolvable hard material, are attachedto an exterior surface of the tissue expander or underneath the exteriorsurface of the tissue expander, and are in the form of dissolvable tabs,clips, balls, or buttons. In some embodiments, the one or more samplesof graft material comprise one or more holes, slits, or aperturesthrough which the attachment points are passed to secure the graftmaterial to the tissue expander. In some embodiments, the attachmentpoints dissolve or otherwise detach after a period of time followingimplantation, thereby releasing the graft material.

In certain embodiments, a prosthesis further comprises one or moremagnets that secure the graft material to the tissue expander. In someembodiments, the prosthesis also comprises a biocompatible flap and twoor more magnets, wherein at least one magnet is secured to a surface ofthe tissue expander and at least one magnet is secured to the flap onthe tissue expander, and wherein the graft material is secured betweenthe two magnets.

In various embodiments, the graft material comprises an acellular tissuematrix. For example, the acellular tissue matrix can comprise an adiposeacellular tissue matrix that has been treated to produce athree-dimensional porous or sponge-like material.

In various embodiments, a method of making an implantable prosthesis isdisclosed, comprising attaching one or more samples of graft material toa tissue expander comprising at least one of: one or more moldedgrooves, slots, channels or other shallow cavity spaces; a flap orpocket; one or more fixation tacks; one or more zip ties; a belt; one ormore attachment points; or one or more magnets. In some embodiments, thegraft material is secured to the tissue expander by interacting with theone or more molded grooves, slots, channels or other shallow cavityspaces; flap or pocket; belt; one or more fixation tacks; one or morezip ties; one or more attachment points; or one or more magnets. In someembodiments, after attaching the graft material to the shell of thetissue expander, the prosthesis is heat cured. In some embodiments, theprosthesis is heat cured at a temperature of about 30° C. or less, or ata temperature of between about 70° C. and 120° C.

Furthermore, in various embodiments, methods of treatment using thedisclosed prostheses are provided herein, comprising implanting aprosthesis into a tissue and then removing the tissue expander after apredetermined length of time while leaving the one or more samples ofgraft material at the implant site. In some embodiments, the tissueexpander separates from the graft material over time followingimplantation without requiring surgical intervention. In otherembodiments, the tissue expander is manually separated from the graftmaterial prior to removal of the tissue expander. In certainembodiments, a prosthesis as disclosed herein is implanted as part of abreast augmentation procedure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates a portion of a prosthesis, according to certainembodiments of the disclosure, comprising a tissue expander having agrooved surface and a graft material shaped to conform to the grooves.FIG. 1B shows the graft material secured to the grooves on the tissueexpander.

FIG. 2 illustrates a portion of a prosthesis, according to certainembodiments, comprising a tissue expander having a polymeric flap,wherein the flap serves to secure a graft material to the surface of theprosthesis.

FIG. 3 illustrates a portion of a prosthesis, according to certainembodiments, comprising a tissue expander having two thin polymericcords that can be passed through holes in a graft material and attachedto the surface of the tissue expander using fixation tacks provided atthe ends of the thin polymeric cords.

FIG. 4 illustrates a portion of a prosthesis, according to certainembodiments, comprising a tissue expander having two zip ties that canbe passed through holes in a graft material and thereby secure the graftmaterial to the tissue expander.

FIG. 5A illustrates a portion of a prosthesis, according to certainembodiments, comprising a tissue expander having a polymeric belt usedto secure a graft material to the tissue expander. FIG. 5B illustrates aportion of a prosthesis, according to certain embodiments, comprising atissue expander having a polymeric belt comprising slots used to securea graft material to the tissue expander. FIG. 5C illustrates a portionof a graft material, according to certain embodiments, shaped to havecomponents that will fit into the slots in the belt shown in FIG. 5B.

FIG. 6 illustrates a portion of a prosthesis, according to certainembodiments, comprising a tissue expander having a flap of biocompatiblematerial and two magnets used to secure the open end of the flap to thetissue expander.

FIG. 7A-C illustrates portions of prostheses, according to certainembodiments, comprising tissue expanders having examples of threedifferent types of attachment points for use in securing a graftmaterial to the tissue expander. FIG. 7D illustrates a portion of agraft material, according to certain embodiments, having holes for usein securing the graft material to the tissue expanders shown in FIG.7A-C.

DESCRIPTION OF CERTAIN EXEMPLARY EMBODIMENTS

Reference will now be made in detail to certain exemplary embodiments ofthe invention, certain examples of which are illustrated in theaccompanying drawings.

In this application, the use of the singular includes the plural unlessspecifically stated otherwise. In this application, the use of “or”means “and/or” unless stated otherwise. Furthermore, the use of the term“including,” as well as other forms, such as “includes” and “included,”is not limiting. Any range described herein will be understood toinclude the endpoints and all values between the endpoints. Also, termssuch as “element” or “component” encompass both elements and componentscomprising one subunit and elements and components that comprise morethan one subunit, unless specifically stated otherwise. Also, the use ofthe term “portion” may include part of a moiety or the entire moiety.

The section headings used herein are for organizational purposes onlyand are not to be construed as limiting the subject matter described.All documents, or portions of documents, cited in this application,including but not limited to patents, patent applications, articles,books, and treatises, are hereby expressly incorporated by reference intheir entirety for any purpose.

The term “graft material,” as used herein, generally refers to abiocompatible material, or a combination of biocompatible materials,such as, for example, one or more samples of tissue, processed tissue,partially or completely decellularized tissue, and/or synthetic materialthat can be attached to a prosthesis, inserted into an implant site, andpromote the migration and/or proliferation of native cells within thegraft material.

The terms “breast implant” and “implant,” as used herein, generallyrefer to medical devices that are implanted either under or withinbreast tissue or under the chest muscle for breast augmentation orreconstruction. Such implants can include saline filled or silicone gelimplants, or other implants that provide volume for breast augmentation.The terms “breast tissue expander,” “tissue expander,” and “expander,”as used herein, generally refer to devices that are implanted under orwithin breast or other tissue or muscle, and which are expanded overtime to stretch breast or other tissue and skin. The tissue expander canbe made from any biocompatible and/or non-reactive material commonlyused in implantable medical devices such as standard tissue expanders orbreast implants. Unless otherwise indicated, different tissue expanderscan be used interchangeably with the different graft materials andmethods disclosed herein. Furthermore, the term “prosthesis” will beunderstood to include any implantable device disclosed herein thatcomprises a tissue expander component and one or more samples of graftmaterial.

The term “resorbable biocompatible polymer,” as used herein, refers to apolymer that can be dissolved or otherwise absorbed by the body overtime following implantation and which does not elicit a substantialimmune or inflammatory response following implantation. A substantialimmune or inflammatory response includes any response that prevents orhinders the migration of native cells into the extracellular matrix ofthe graft material or prevents the partial or complete repopulation ofthe graft material with native cells. For example, the resorbablepolymer can comprise aliphatic polyester polymers and copolymers andblends thereof, polymers of lactide or galactide or copolymers thereof,polysaccharides such as cellulose, oxidized polysaccharides, or otherabsorbable polymers. As used herein, the terms “native cells” and“native tissue” mean the cells and tissue present in the recipienttissue/organ prior to the implantation of a prosthesis, or the cells ortissue produced by the host animal after implantation

The present disclosure relates to prostheses, methods of makingprostheses, and methods of treatment using the prostheses. In variousembodiments, the prostheses disclosed herein can be used with anysurgical procedure where tissue expansion is desirable (e.g., to stretchtissue harvested for use in autologous skin grafts). As such, theimplantable prostheses and methods discussed herein may be suitable fora wide range of surgical applications. In some embodiments, theprostheses and methods discussed herein may be suitable for varioustypes of surgical breast procedures, such as, for example, aestheticsurgery associated with mastectomy or lumpectomy, breast reconstruction,breast augmentation, breast enhancement, mastopexy, and/or revisionarybreast surgeries.

According to certain embodiments, a prosthesis is disclosed. Theprosthesis can comprise a tissue expander and one or more samples ofgraft material, wherein the tissue expander is attached to the one ormore samples of graft material in a manner that allows the tissueexpander and the one or more samples of graft material to be implantedin a patient as a unitary prosthesis; and wherein the implant or tissueexpander is attached to the one or more samples of graft material in amanner that will allow the tissue expander and the graft material to beeasily separated after a period of time following implantation. Thetissue expander can be made from any biocompatible and/or non-reactivematerial commonly used in implantable medical devices such as standardtissue expanders or breast implants.

In certain embodiments, the structure of the tissue expander, along withits attachment to a graft material such as an acellular tissue matrix,allows the tissue expander to be enlarged and subsequently removed aftera certain period of time, without removing the graft material.Accordingly, the devices and methods of the present disclosure can bebeneficial for reconstruction procedures that require removal of tissueexpanders but where retention of a graft material would be desirous.

By providing a tissue expander and one or more samples of graft materialas a unitary prosthesis, the implantable prostheses of the presentdisclosure can, in some embodiments, shorten procedure time, reduce thenumber of surgical sutures, staples and/or other attachment devicesneeded to secure the prostheses, and reduce the associated costs ofsurgery. In certain embodiments, the implantable prostheses can alsoimprove surgical outcomes and improve consistency of results. In someembodiments, the implantable prostheses reduce the incidence ofextrusion and/or capsular contraction, block or reduce inflammatoryresponses, and/or result in shorter expansion times.

In some embodiments, the tissue expanders can be implanted as unitaryprostheses. In some embodiments, the implantable prostheses of thepresent disclosure can be constructed such that the tissue expander caneasily separate from the graft material after implantation. In variousembodiments, the graft material is attached to the tissue expander insuch a way that the two will separate before the tissue expander isremoved. In some embodiments, the tissue expander is designed toseparate from the graft material after a period of time. In certainembodiments, the graft material is attached to the tissue expander insuch a way that the graft material and tissue expander will separatewithout requiring surgical intervention. In other embodiments, the graftmaterial is attached to the tissue expander in such a way that the twocan be easily separated when the tissue expander is surgically removed,leaving the graft material at the implant site.

According to certain embodiments, a prosthesis is disclosed thatcomprises a tissue expander and one or more samples of graft materialsized and/or shaped to conform to a portion of a surface of the tissueexpander, wherein the one or more samples of graft material is attachedto the tissue expander in such a way as to temporarily secure the graftmaterial in place but to release the graft material from the tissueexpander over time following implantation.

For example, in some embodiments, a tissue expander may comprise moldedgrooves, slots, channels or other shallow cavity spaces on the surfaceof the expander. For instance, FIG. 1A illustrates a portion of a tissueexpander having a surface 103 containing grooves 101. Graft material104, optionally containing shaped components 102 that conform to thegrooves 101 or other cavity spaces, can be placed within the cavityspaces in the tissue expander. In some embodiments, the graft material104 is initially held in place by the edges of the cavity spaces in thetissue expander (FIG. 1B), which press against all or some of the graftmaterial 104 and provide a frictional force to prevent the graftmaterial 104 from migrating away from the expander. Over time, the graftmaterial 104 can separate from the tissue expander. For example, thegraft material 104 may naturally migrate away from the expander as thefrictional force holding it in place lessens after implantation (e.g.,due to the aqueous environment, due to the deformation of the expanderor the graft material following implantation, and/or due to the naturalflexibility of the grooves, slots, channels or other shallow cavityspaces). Alternatively, in some embodiments the graft material 104 maybe released from the cavity spaces as the tissue expander is filledafter implantation, thereby stretching the edges of the cavity space andremoving the frictional force securing the graft material 104 to theexpander.

In another example, a graft material can be secured to a tissue expanderby a flap or pocket of biocompatible material on the surface of thetissue expander. In some embodiments, the flap or pocket is secured atone end but able to slide relative to the underlying surface of thetissue expander. For example, FIG. 2 illustrates a portion of aprosthesis 201 comprising a tissue expander 202 having a polymeric flapor pocket 204, wherein the flap or pocket 204 serves to secure a graftmaterial 203 to the surface of the tissue expander 202. The flap orpocket 204 can comprise a biocompatible material (e.g., silicone). Thegraft material 203 can be placed in the flap or pocket 204, temporarilysecuring the graft material 203 to the expander 202. As the tissueexpander 202 is filled, the flap or pocket 204 is retracted, releasingthe graft material 203.

In yet another example, a graft material can be secured to a tissueexpander using fixation tacks. For example, a tissue expander cancomprise one or more thin cords or strands of biocompatible material(e.g., silicone). In some embodiments, the cords can have a branchedstructure, such as a T-tack structure. In certain embodiments, the endsof the cords can comprise tacks or other textured surfaces that canengage the surface of a tissue expander and/or a graft material. In someembodiments, a graft material comprising at least one hole is secured tothe tissue expander by passing the one or more cords or strands throughthe at least one hole in the graft material. In certain embodiments, thetacks or textured surface on the end of the cord or strand is placed incontact with the tissue expander or graft material after being passedthrough the one or more holes on the graft material, anchoring the graftmaterial to the expander. In some embodiments, the graft materialcomprises at least two holes, and the cords or strands are threadedthrough both holes, thereby anchoring the graft to the underlyingexpander. In various embodiments, filling the tissue expander exertstension on the cords or strands, causing the tacks or other texturedsurfaces to release, thereby freeing the graft material from the tissueexpander. In other embodiments, the cords or strands comprise aresorbable polymer (e.g., aliphatic polyester polymers, copolymers,blends thereof, polymers of lactide, galactide, or copolymers thereof,polysaccharides such as cellulose, and oxidized polysaccharides, orother absorbable polymers) that dissolves over time followingimplantation, thereby releasing the graft material. For example, FIG. 3illustrates a portion of a prosthesis 301 comprising a tissue expander302 having two thin polymeric cords 304 that pass through holes 305 in agraft material 306 and attach to the surface of the tissue expander 302using fixation tacks 303.

In still another example, a graft material can be secured to a tissueexpander using zip ties. For example, a tissue expander comprising oneor more attached zip ties can be prepared. The zip ties can comprise abiocompatible material (e.g., silicone). In some embodiments, the zipties are passed through one or more holes in a graft material and thenpassed through the locking point in the zip tie, securing the graftmaterial to the tissue expander. In some embodiments, the zip ties aremanually released by the surgeon prior to surgical removal of the tissueexpander. In another embodiment, the zip ties are prepared from aresorbable, biocompatible material that dissolves over time afterexposure to the aqueous implant environment, thereby releasing the graftmaterial. In certain embodiments, the resorbable polymer can comprisealiphatic polyester polymers, copolymers, blends thereof, polymers oflactide, galactide, or copolymers thereof, polysaccharides such ascellulose, and oxidized polysaccharides, or other absorbable polymers).For example, FIG. 4 illustrates a portion of a prosthesis 401 comprisinga tissue expander 402 having two zip ties 403 that pass through holes404 in a graft material 405 and secure the graft material 405 to thetissue expander 402.

In another example, a tissue expander can comprise a belt used to securea graft material. For example, FIG. 5A illustrates a portion of aprosthesis 501 comprising a tissue expander 502 having a polymeric belt503 used to secure a graft material to the tissue expander 502. Invarious embodiments, the belt 503 may comprise a biocompatible material(e.g., silicone). In some embodiments, the graft material can beinserted under the belt 503, securing the graft to the expander 502. Incertain embodiments, the belt can comprise slots, and the graft materialcan be shaped to provide tabs or other shapes that will fit within theslots on the belt, thereby securing the graft material to the belt. Forexample, FIG. 5B illustrates a portion of a prosthesis 501 comprising atissue expander 502 having a polymeric belt 503 comprising slots 504used to secure a graft material to the tissue expander 502. In someembodiments, a graft material, such as the graft material 506 shown inFIG. 5C, is shaped to have components 505 that will fit into the slots504 in the belt 503, thereby securing the graft material 506 to thetissue expander 502.

In some embodiments, as the tissue expander is filled, the belt thatsecures the graft to the expander is stretched, reducing the tensionapplied by the belt on the graft material, and thereby releasing thegraft material from the tissue expander. In other embodiments, the graftmaterial is manually released from the belt by the surgeon when thetissue expander is removed. In other embodiments, the belt comprises aresorbable polymer (e.g., aliphatic polyester polymers, copolymers,blends thereof, polymers of lactide, galactide, or copolymers thereof,polysaccharides such as cellulose, and oxidized polysaccharides, orother absorbable polymers) that dissolves over time followingimplantation, thereby releasing the graft material.

In various embodiments, a tissue expander can comprise attachment points(e.g., clips, balls, buttons or tabs) on at least a portion of the outersurface. For example, FIG. 7A-C illustrates portions of tissue expandershaving three different types of attachment points 701, 702, and 703 foruse in securing a graft material to the tissue expander. The attachmentpoints 701-703 can be used to secure the graft material to the expander,for example by folding over the edges of the graft material, or bypushing the attachment points 701-703 through holes, slits, or otherperforations placed in the graft material, thereby securing the graftmaterial in place. For example, FIG. 7D illustrates a portion of a graftmaterial 704 having holes 705 through which the attachment points701-703 can be passed to secure the graft material 704 to the tissueexpander. The attachment points 701-703 can have any shapes suitable forsecuring a graft material, for example balls, cylinders, cylinders withwidened heads, button, curved shapes, etc. Over time, the attachmentpoints 701-703 are designed to dissolve, separate, detach, or otherwiserelease the graft material 704 from the tissue expander.

For example, in certain embodiments a hard material can be placedunderneath the outer membrane of the tissue expander and press outthrough the membrane to create the attachment points. For example, ahard material in the shape of tabs, clips, balls, buttons, or otherdesired shapes can be affixed along the inner surface of the expanderand bulge out through the membrane to create attachment points for thegraft material. The hard material can be used to secure the graftmaterial to the expander, for example by folding over the edges of thegraft material, or by pushing through holes, slits, or otherperforations placed in the graft material, thereby securing the graftmaterial in place. In some embodiments, the hard material comprises amaterial that is soluble in aqueous solution. Over time, the saline orother aqueous solution in the tissue expander can dissolve the hardmaterial, thereby releasing the graft material. Examples of suitablehard materials include, but are not limited to, poly-caprolactone,polylactic acid, polygalacturonic acid, polymer polyglycolic-lacticacid, polyhydroxyalkanoates, polydioxanone, or any other similarpolymers or biological materials known to degrade in vivo.

In another example, the attachment points can comprise a hard materialattached to the external surface of a tissue expander. In someembodiments, the attachment points comprise tabs, clips, balls, buttons,or other desired shapes that secure the graft material to the expander,for example by folding over the edges of the graft material, or bypushing through holes, slits, or other perforations placed in the graftmaterial, thereby securing the graft material in place. In someembodiments, the attachment points are designed to release when exposedto force as the tissue expander is filled. For example, filling thetissue expander can lift or stretch the tabs that hold a graft materialagainst a tissue expander, bending the tabs away from the graft materialand releasing the graft material from the expander. Similarly, inanother example, filling the tissue expander can stretch the graftmaterial secured to it, thereby transmitting a torsional force to theattachment points (e.g., the tabs, clips, balls, buttons, or othershapes) as the graft material pulls on them, resulting in thedeformation or detachment of the attachment points and release of thegraft material. In other embodiments, the attachment points may comprisea resorbable, biocompatible material that dissolves over time whenexposed to the aqueous environment of the implant site, therebyreleasing the graft material. For example, the resorbable material cancomprise aliphatic polyester polymers, copolymers, blends thereof,polymers of lactide, galactide, or copolymers thereof, polysaccharidessuch as cellulose, and oxidized polysaccharides, or other absorbablepolymers that dissolve over time following implantation, therebyreleasing the graft material.

In various embodiments, a graft material can be secured to a tissueexpander using one or more magnets. For example, FIG. 6 illustrates aportion of a prosthesis 601 comprising a tissue expander 602 having aflap 604 of biocompatible material and two magnets 603, with one portionof the magnet 603 secured to the inner surface of the tissue expander602 and the other portion of the magnet 603 secured to the flap 604 ofthe tissue expander 602. In some embodiments, a graft material can beplaced over the tissue expander 602 or over a portion of the tissueexpander 602 comprising the at least one magnet 603. The flap 604comprising at least one magnet 603 can be folded down over the graftmaterial to interact with the magnet 603 on the inner surface of thetissue expander 602, thereby securing the graft material between theflap 604 and the tissue expander 602. In some embodiments the one ormore magnets and the flap comprise biocompatible materials.

According to certain embodiments, a method of making a prosthesis isprovided. The method can comprise providing a tissue expander and one ormore samples of graft material that is sized and/or shaped to conform toat least a portion of a surface of the tissue expander, and attachingthe one or more samples of graft material to the tissue expander usingone of the attachment methods described above. The tissue expandersdisclosed herein can be formed from a variety of suitable materials. Forexample, the shell of an expander may be produced from a material thatis designed to prevent tissue ingrowth and/or adhesion, and which canexpand when placed under force during filling. For example, in someembodiments, a tissue expander can be formed from a material thatprovides a smooth shell, such as silicone. In other embodiments, atissue expander is made from a material that provides a desired surfacetexture, or the tissue expander is molded during formation to provide adesired surface texture.

In some embodiments, the tissue expander can be attached to the one ormore samples of graft material in a medical setting or in the operatingroom just prior to implanting a prosthesis in a patient. In someembodiments, the tissue expander can be attached to the one or moresamples of graft material prior to a surgery. In some embodiments, thetissue expander can be attached to the one or more samples of graftmaterial prior to the surgery, so that the implantable prosthesis can besold as a ready-to-use, off the shelf prosthesis. In some embodiments, apackage or kit can comprise a prosthesis, comprising the tissue expanderpre-attached to the one or more graft materials, or provided as twoseparate components within the package or kit. In some embodiments, theprosthesis in the kit is packaged under aseptic or sterile conditions.In certain embodiments, the kit can further comprise instructions forusing the tissue expander.

In various embodiments, the graft materials are further secured to thetissue expander using biodegradable sutures, biocompatible adhesives,biocompatible glues, and/or any means of attachment known by one ofskill in the art.

According to certain embodiments, methods of making a prosthesis aredisclosed, comprising preparing a tissue expander, providing one or moresamples of graft material sized and shaped to conform to at least aportion of a surface of a tissue expander, attaching the graft materialto the shell of the tissue expander using any of the attachment methodsdescribed above to form a prosthesis, and optionally curing and/orirradiating the prosthesis.

In some embodiments the graft material comprises an acellular tissuematrix. In some embodiments the graft material comprises an acellulartissue matrix that has been treated to produce a three-dimensionalporous, or sponge-like material.

In some embodiments the shell of the tissue expander and the acellulartissue matrix are cured such that the curing temperature does not reacha temperature greater than 30° C. In some embodiments the shell of thetissue expander and the acellular tissue matrix are cured such that thecuring temperature does not exceed 25° C. In some embodiments the shellof the tissue expander and the extracellular tissue matrix are curedsuch that the curing temperature is between about 70° C. and 120° C., orbetween about 80° C. and 110° C., or about 100° C. In some embodimentslower or higher temperatures could be used as long as melting of thematrix proteins does not occur.

The graft materials and tissue expanders discussed herein can includeone or more biocompatible materials. The biocompatible material cancomprise any suitable synthetic or biologic material, such as, forexample, medical grade silicone, autologous or cadaveric tissue, and/orbiomatrices, such as, for example, an acellular tissue matrix (“ATM”).In some embodiments, the biocompatible material may be a flat sheet orsheet-like in form. A biocompatible material may be a single layer ormay be multi-layered. In some embodiments, a biocompatible material maybe a material that facilitates cell migration, repopulation, and/orrevascularization. For example, in certain embodiments, a graft materialcan include an acellular tissue matrix (“ATM”).

As used herein, ATM refers to a tissue-derived biomatrix structure thatcan be made from any of a wide range of collagen-containing tissues byremoving all, or substantially all, viable cells and all detectablesubcellular components and/or debris generated by killing cells. As usedherein, an ATM lacking “substantially all viable cells” is an ATM inwhich the concentration of viable cells is less than 1% (e.g., lessthan: 0.1%; 0.01%; 0.001%; 0.0001%; 0.00001%; or 0.000001%; or anypercentage in between) of the viable cells in the tissue or organ fromwhich the ATM was derived.

For a description of exemplary ATMs that are suitable for use in thepresent disclosure, as well as methods of making those ATMs, seeco-pending U.S. application Ser. No. 12/506,839 (published as US2011/0022171) at paragraphs 41-73 and U.S. Provisional Application No.61/491,787 at paragraphs 23-38 and 42-56, which are incorporated hereinby reference in their entirety. Additionally, as non-limiting examplesof methods of producing ATMs, mention is made of the methods describedin U.S. Pat. Nos. 4,865,871; 5,366,616; and 6,933,326, and U.S. PatentApplication Publication Nos. US2003/0035843 A1, and US 2005/0028228 A1,all of which are incorporated herein by reference in their entirety.

In some embodiments, the graft material can comprise STRATTICE™, aporcine dermal tissue produced by Lifecell Corporation (Branchburg,N.J.). In some embodiments, the graft material can comprise ALLODERM®,an ATM produced from human dermis by LifeCell Corporation (Branchburg,N.J.).

In some embodiments, the graft material comprises an adipose tissuematrix. In some embodiments the graft material comprises an adiposetissue matrix that has been treated to produce a three-dimensionalporous, or sponge-like material. For a description of adipose tissuematrices that are suitable for use in the present disclosure, as well asmethods of making adipose tissue matrices, see U.S. ProvisionalApplication No. 61/491,787 at paragraphs 23-38 and 42-56, which isincorporated by reference in its entirety. Briefly, the processgenerally includes obtaining adipose tissue, mechanically processing theadipose tissue to produce small pieces, further processing the tissue toremove substantially all cellular material and/or lipids from thetissue, resuspending the tissue in a solution to form a porous matrix orsponge, and optionally cross-linking the tissue to stabilize a desiredthree-dimensional structure.

In certain embodiments, ready-to-use, off-the-shelf materials that aredesigned or further processed to conform to tissue expanders of variousspecifications can be used as graft materials. For a description ofmethods of making graft materials that are suitable for use in thepresent disclosure, see co-pending U.S. application Ser. No. 12/506,839(published as US 2011/0022171). The disclosure of U.S. application Ser.No. 12/506,839 is incorporated herein by reference in its entirety.

In certain embodiments, methods of treatment are provided, comprisingproviding any of the prostheses described above and implanting theprosthesis into a site on a patient where a prosthesis is required(e.g., as part of a breast augmentation procedure). In certainembodiments, a prosthesis is used following a breast cancer therapy(e.g., to expand remaining native skin to receive a breast implantfollowing a mastectomy). In other embodiments, a prosthesis is used aspart of a cosmetic procedure (e.g., as part of a breast alterationprocedure).

Other embodiments of the invention will be apparent to those skilled inthe art from consideration of the specification and practice of theinvention disclosed herein. It is intended that the specification andexamples be considered as exemplary only, with a true scope and spiritof the invention being indicated by the following claims.

What is claimed is:
 1. A prosthesis comprising: a tissue expander; andone or more samples of graft material releasably coupleable to thetissue expander in a manner that allows the tissue expander and thegraft material to be implanted in a patient as a unitary prosthesis andin a manner that will permit the tissue expander to separate from thegraft material after a period of time following implantation to allowremoval of the tissue expander from an implant site while leaving thegraft material within the implant site; wherein the prosthesis comprisesone or more elongated fasteners to secure the graft material to thetissue expander; and wherein the graft material is configured to releasefrom the tissue expander due to tension on the one or more elongatedfasteners, the tension caused by enlargement of the tissue expanderafter implantation.
 2. The prosthesis of claim 1, wherein the one ormore samples of graft material comprise acellular tissue matrix.
 3. Theprosthesis of claim 1, wherein the one or more samples of graft materialcomprise dermal tissue matrix.
 4. The prosthesis of claim 2, wherein theacellular tissue matrix comprises an adipose acellular tissue matrix. 5.The prosthesis of claim 1, wherein the one or more elongated fastenerscomprise silicone.
 6. The prosthesis of claim 1, wherein the one or moreelongated fasteners comprise a resorbable synthetic material.
 7. Theprosthesis of claim 6, wherein the one or more elongated fastenersdissolve over a period of time following implantation after exposure toan aqueous implant environment such that the tissue expander is releasedfrom the graft material.
 8. The prosthesis of claim 1, wherein the oneor more samples of graft material comprise one or more holes, slits, orapertures through which the one or more elongated fasteners are passedto secure the graft material to the tissue expander.
 9. The prosthesisof claim 1, wherein the tissue expander comprises exactly two elongatedfasteners that can be passed through holes in the graft material tosecure the graft material to the tissue expander.